The most important function of teeth is to chew. The object of treating decayed teeth is to restore as natural occlusion as possible. There are stereo articulators of a type in which the simulation of dental occlusion is possible and in virtue of this, removable partial dentures and full dentures, bridges and crowns, of which the functions are matched to that of the human tooth can be manufactured. A variety of stereo articulators of this type have been developed, for example, as described in "Dictionary of Dental Occlusion" (issued on Mar. 20, 1979 by Shorin Co., Ltd.).
Of these are extensively known the so-called arcon full-adjustable articulator comprising an upper frame member with a condylar guide part, which is a path along which the capitulum mandible travels as the mandible moves, and a lower frame member with a condyle part, and also a simulator articulator where the structural parts can be adjusted to average values of anatomy.
The structure in human permits the lower jaw to swing around the movable fulcrum on the maxilla while the arcon full-adjustable articulator has the construction that the upper frame member moves around the condyle part on the lower frame.
All the conventional articulators mentioned above are of the type in which, unlike the structure in human, the upper frame moves. Viewing from the structure in human, the practical measurement data of inclination of condyle path, and sideward, forward and opening movements has revealed that they were very unnatural, and besides dynamical study on occlusion buffer has demonstrated that partial pressure on teeth was distributed. For these reasons, the structure remained as a basic problem. Also another type of articulator has been developed intending to solve this problem which comes from the construction that the movable frame members were disposed reversely to the structure in the human and therefore in which a condyle is provided on the upper frame member to permit the lower frame member to be movable.
Occlusal movement in the human is very complicated, and hence to realize a physiological stereo articulator of the type in which the lower frame member is movable is not simple to such an extent that to the contrary of the arcon full-adjustable articulator, a condyle is fixed to the upper frame member instead of the upper frame but it is required to be a structure permitting the lower frame member to completely simulate the real condyle path.
The principal object of the present invention is to provide a physiological stereo articulator comprising a lower frame member movable conforming with the most fidelity the condyle path in the human.